By Ashley Nee The most severe Ebola outbreak in the Democratic Republic of the Congo (DRC) has been ravaging the country since August of this year, with 319 probable cases and 198 fatalities. [1] The scale of this outbreak, exacerbated by internal DRC conflict and resistance, has led the director of the Centers for Disease Control and Prevention (CDC) to warn that if Ebola were to become endemic to the area, then “this [would] mean that we've lost the ability to trace contacts, stop transmission chains, and contain the outbreak.” [2] Such a warning is terrifying, not only for those living in the DRC, but also for countries across the globe. In our modern world, it is easy and efficient for people and goods to travel thousands of miles with the advent of airplanes and more advanced shipping technology. We are more connected than ever, but this connection also offers pathogens opportunities to stowaway and spread. A famous example of this phenomena was the 2002-2004 SARS outbreak. Beginning in southern China, SARS radiated out to 30 other countries and resulted in the deaths of over 800 patients. The 2002-2004 SARS outbreak had the potential to be the next “big one” in disease; the term “big one” in disease was popularized by science writer David Quammen and meant to encapsulate the idea of a pandemic capable of causing illness and death across the globe. Like SARS and other emerging diseases deemed “big one” candidates, Ebola is a zoonotic disease, meaning that both transferred from a nonhuman animal host to humans. Thus, Ebola’s current potential to become uncontainable makes combatting it an especially critical matter. In spite of difficulties in dealing with violent conflict in the DRC, there is hope in recombinant vesicular stomatitis virus–Zaire Ebola virus (rVSV-ZEBOV), an Ebola vaccine developed by the pharmaceutical company Merck. The vaccine is recombinant, meaning that it has been genetically modified; in this case, the genetic material of the vesicular stomatitis virus has been rearranged to present a glycoprotein specific to that of the Zaire strain of Ebola virus, which is endemic to the DRC. [3] The presentation of a glycoprotein specific to Zaire ebola virus provides the human immune system with a “flag” to look out for and attack if it is detected. In the Phase III clinical trial for rVSV-ZEBOV vaccine, the point estimate for the vaccine’s efficacy was measured as 100%, as no new Ebola cases occurred in vaccinated trial groups. However, this figure of 100% efficacy was criticized in a review by the U.S. National Academy of Science as unsubstantiated due to the lack of a placebo arm and the elimination of a delayed treatment group as a control in the final statistical analysis. [4] Further, interpretations of the trial are indeterminate, meaning that it is unclear whether rVSV-ZEBOV vaccine has any significant protective effect against Ebola. Still, the vaccine was used in an earlier 2018 Ebola outbreak and seemed to be effective in use. It is being used again during this most current outbreak. Uganda, while still unaffected by this most recent Ebola outbreak, has preemptively begun issuing rVSV-ZEBOV vaccinations due to the high risk Ebola has of spilling over there. [5] Due to the questionable efficacy of rVSV-ZEBOV and violent complications in the DRC, a clear action plan is necessary to ensure the success of Ebola containment both now and in the future. Such an action plan may include the implementation of stricter restrictions on flights and exports from the DRC as well as an increase in volunteer efforts and support from doctors and other healthcare professionals. Long-term, setting up educational facilities in the DRC to inform individuals of preventive measures against Ebola and to create solutions for preventive measures that might impede lifestyle (i.e. avoiding bushmeat consumption and creating solutions for people who rely on bushmeat for sustenance and cultural traditions) may also be beneficial. Still, the conflict that also plagues the DRC must somehow be circumvented in order to contain Ebola now. If we fail to act with expediency and care, we risk the lives of not just people in the DRC and surrounding countries but potentially people around the world. Sources: [1] Center for Infectious Disease Research and Policy, University of Minnesota. Ebola outbreak now DRC's largest ever, with 319 cases [Internet]. 2018 [Cited 2018 Nov 10]. Available from: http://www.cidrap.umn.edu/news-perspective/2018/11/ebola-outbreak-now-drcs-largest-ever-319-cases [2] Inglesby Tom. Interviewed by: Writer at the Washington Post. November 5, 2018 [Cited November 9, 2018]. [3] Regules J A, Beigel J H, Paolinio K M, Voell J, Castellano A R, Muñoz P, et al. A Recombinant Vesicular Stomatitis Virus Ebola Vaccine — Preliminary Report. The New England Journal of Medicine [Internet]. 2015 [cited Nov 9, 2018]. DOI: 10.1056/NEJMoa1414216. [4] Integrating Clinical Research into Epidemic Response: The Ebola Experience [Internet]. The National Academies of Health and Science [cited Nov 17, 2018]. Available from: http://nationalacademies.org/hmd/Reports/2017/integrating-clinical-research-into-epidemic-response-the-ebola-experience.aspx [5] Molteni M. The Risk that Ebola will Spread to Uganda is now ‘Very High’ Wired [Internet] 2018 Nov 12 [Cited 2018 Nov 12]. Available from: https://www.wired.com/story/the-risk-that-ebola-will-spread-to-uganda-is-now-very-high/
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